Ribbon like filaments and systems and methods for producing the same

ABSTRACT

Various implementations include a melt-spun filament that has a radial cross section that has two substantially parallel linear perimetrical sections and first and second curved perimetrical sections. The first curved perimetrical section extends between first ends of the linear perimetrical sections, and the second curved perimetrical section extends between second ends of the linear perimetrical sections. The curved perimetrical sections are convex. According to some embodiments, the curved perimetrical sections are semi-circular or semi-elliptical. A plurality of melt-spun filaments may be included in a bundle of filaments and/or a yarn made with the melt-spun filaments. In addition, a spinneret plate for spinning the melt-spun filaments and a method of making the melt-spun filaments is also provided.

BACKGROUND

Trilobal and round shaped filaments provide a soft hand feel, but these filaments are prone to breaking during processing. Rectangular shaped filaments have a less soft hand feel but are less prone to breaking during processing. Thus, there is a need in the art for a filament that provides the soft hand feel of trilobal and round shaped filaments but has the durability of rectangular shaped filaments.

BRIEF SUMMARY

According to a first aspect, a melt-spun filament is provided that has a radial cross section that has two substantially parallel linear perimetrical sections and first and second curved perimetrical sections. The first curved perimetrical section extends between first ends of the linear perimetrical sections, and the second curved perimetrical section extends between second ends of the linear perimetrical sections. The curved perimetrical sections are convex.

According to some embodiments, the radial cross section is capsule shaped.

According to some embodiments, the radial cross section is rice shaped. According to some embodiments, a plane extends axially through the melt-spun filament, intersects the curved perimetrical ends, and includes a central axis of the filament, and a line that is tangential to one of the ends of the linear perimetrical sections intersects the plane at an angle of between 0° and 10°.

According to some embodiments, the melt-spun filament further comprises a core and a sheath disposed around the core. The core is formed from a first material, and the sheath is formed from a second material. According to some embodiments, the first material and the second material are different. For example, according to some embodiments, the first material and the second material are selected from different types of polymers and/or different resin grades (e.g., virgin or reclaim). And, in certain embodiments, the first material and second material are selected from the group consisting of polytrimethylene terephthalate (PTT), polyethylene terephthalate (PET), polyamides (PA), Polybutylene terephthalate (PBT), and other polyesters and polyolefins. Example polyamides include nylon 6 and nylon 6,6. Example polyolefins include polypropylene (PP) and polyethylene (PE). And, in some embodiments, the first or second material may include a polyolefin and a carbon filler to produce an antistatic yarn.

According to some embodiments, the melt-spun filament further comprises a first material and a second material. The first material and second material are coupled along a plane that includes the axis of the filament, and the first material and second material have different coefficients of thermal expansion. For example, according to some embodiments, the first material and the second material are selected from the group consisting of polytrimethylene terephthalate (PTT), polyethylene terephthalate (PET), polyamides (PA), Polybutylene terephthalate (PBT), and other polyesters and polyolefins. Example polyamides include nylon 6 and nylon 6,6. Example polyolefins include polypropylene (PP) and polyethylene (PE). And, in some embodiments, the first or second material may include a polyolefin and a carbon filler to produce an antistatic yarn.

According to some embodiments, the filament comprises a thermoplastic material.

According to some embodiments, a width to height ratio of the radial cross section of the filament is between 3.5:1 and 1.5:1, wherein the width is measured in a direction of the linear perimetrical sections at the widest points of the radial cross section and the height is measured in a direction perpendicular to the width direction. For example, according to some embodiments, the width to height ratio of the radial cross section is between 3:1 and 2.2:1.

According to some embodiments, the curved perimetrical sections are semi-circular.

According to some embodiments, the curved perimetrical sections are semi-elliptical.

According to some embodiments, the melt-spun filament is converted into a plurality of staple fibers.

According to a second aspect, a spun yarn of the staple fibers is provided.

According to a third aspect, a bundle of filaments comprising a plurality of the melt-spun filaments is provided.

According to a fourth aspect, a filament yarn comprising a plurality of the melt-spun filaments is provided.

According to a fifth aspect, a bulked continuous filament yarn comprising a plurality of the melt-spun filaments is provided.

According to a sixth aspect, a spinneret plate is provided for producing the melt-spun filament. The spinneret plate comprises one or more capillaries, and each capillary has a rectangular shaped outlet opening.

According to a seventh aspect, a method of making the melt-spun filament is provided. The method includes (1) providing a spinneret plate comprising one or more capillaries, each capillary having a rectangular shaped outlet opening; and (2) feeding at least one melted thermoplastic polymer through the capillary.

According to an eighth aspect, a spinneret plate for producing a melt-spun filament is provided. The spinneret plate comprising at least one capillary comprising, a first section comprising a counterbore with vertical sides, a second section comprising angled sides of a first angle, a third section comprising vertical sides, a fourth section comprising angled sides of a second angle, wherein a cross-section of the at least one capillary comprises a rectangle.

According to a ninth aspect, a method for producing a melt-spun filament from a capillary of the spinneret place of the eight aspect is provided. The method comprising pumping a polymer melt into the capillary at a first speed to produce a filament having a first filament aspect ratio at the spinneret plate, drawing the filament at a first draw rate from the spinneret plate such that the filament has a second filament aspect ratio at a point further away from the spinneret plate.

According to a tenth aspect, a capillary in a spinneret plate for producing a melt-spun filament is provided. The capillary comprising a rectangular opening with a first section comprising a counterbore with substantially vertical sides, a second section adjoining the first section, wherein the second section comprises sides that are angled away from the vertical sides of the first section at a first angle, a third section adjoining the second section, wherein the third section comprises sides that are substantially parallel to the sides of the counterbore, a fourth section adjoining the third section, wherein the fourth section comprises sides that are angled away from the vertical sides of the third section at a second angle.

According to an eleventh aspect, a method for producing a melt-spun filament is provided. The method comprising providing a spinneret plate comprising at least one capillary, wherein the capillary comprises, a rectangular opening with a first section comprising a counterbore having substantially vertical sides that are perpendicular to a face of the spinneret plate, a second section adjoining the first section, wherein the second section comprises sides that are angled away from the vertical sides of the first section at a first angle, a third section adjoining the second section, wherein the third section comprises sides that are substantially vertical, a fourth section adjoining the third section, wherein the fourth section comprises sides that are angled away from the vertical sides of the third section at a second angle, pumping a polymer melt into the fourth section of the capillary at a first speed to extrude a filament from the counterbore, wherein the filament has a first filament aspect ratio at the spinneret plate, drawing the filament at a first draw rate from the spinneret plate such that the filament has a second filament aspect ratio at a point further away from the spinneret plate.

BRIEF DESCRIPTION OF THE DRAWINGS

Example features and implementations are disclosed in the accompanying drawings. However, the present disclosure is not limited to the precise arrangements shown, and the drawings are not necessarily drawn to scale.

FIG. 1 illustrates a radial cross section view of a melt-spun filament according to one implementation.

FIG. 2 illustrates a perspective view of the melt-spun filament shown in FIG. 1 .

FIGS. 3A and 3B illustrate radial cross section views of a plurality of melt-spun filaments spun from a spinneret having a spin slot aspect ratio of 6:1. FIG. 3A shows filaments spun from a spinneret having 87 holes and a denier per filament of 3.8. FIG. 3B shows filaments spun from a spinneret having 120 holes and a denier per filament of 2.8.

FIGS. 4A and 4B illustrate radial cross section views of a plurality of melt-spun filaments spun from a spinneret having a spin slot aspect ratio of 4:1. FIG. 4A shows filaments spun from a spinneret having 87 holes and a denier per filament of 3.8. FIG. 4B shows filaments spun from a spinneret having 120 holes and a denier per filament of 2.8.

FIG. 5A illustrates a radial cross section view of a capillary in a spinneret plate having a spin slot aspect ratio of 4:1, and FIG. 5B illustrates an axial view of the capillary, according to one implementation. FIG. 5C illustrates a plan view of a portion of a spinneret plate defining a plurality of the capillaries shown in FIGS. 5A and 5B.

FIG. 6A illustrates a radial cross section view of a capillary in a spinneret plate having a spin slot aspect ratio of 6:1, and FIG. 6B illustrates an axial view of the capillary, according to one implementation. FIG. 6C illustrates a plan view of a portion of a spinneret plate defining a plurality of the capillaries shown in FIGS. 6A and 6B.

FIG. 7 illustrates a radial cross section view of a melt-spun filament having slightly arcuate shaped linear perimetrical section according to another implementation.

FIG. 8 illustrates a radial cross section view of a melt-spun filament having a core and sheath according to another implementation.

FIG. 9 illustrates a radial cross section view of a melt-spun filament having two materials with differential coefficients of thermal expansion, according to another implementation.

FIG. 10A illustrates a radial cross section view of a capillary in a spinneret plate having a spin slot aspect ratio of 4:1, and FIG. 10B illustrates an axial view of the capillary, according to one implementation. FIG. 10C illustrates a plan view of a portion of a spinneret plate defining a plurality of the capillaries shown in FIGS. 10A and 10B.

FIG. 11A illustrates a radial cross section view of a capillary in a spinneret plate having a spin slot aspect ratio of 6:1, and FIG. 11B illustrates an axial view of the capillary, according to one implementation. FIG. 11C illustrates a plan view of a portion of a spinneret plate defining a plurality of the capillaries shown in FIGS. 11A and 11B.

FIG. 12A illustrates a cross section of an exemplary capillary with a polymer flowing through it; and FIG. 12B illustrates the cross section of the exemplary capillary from a right-angle view from FIG. 12A.

DETAILED DESCRIPTION

Various implementations include a melt-spun filament that has a radial cross section that has two substantially parallel linear perimetrical sections and first and second curved perimetrical sections. The first curved perimetrical section extends between first ends of the linear perimetrical sections, and the second curved perimetrical section extends between second ends of the linear perimetrical sections. The curved perimetrical sections are convex. According to some embodiments, the curved perimetrical sections are semi-circular or semi-elliptical. Various implementations of the melt-spun filament provide a softer hand feel than rectangular shaped filaments, which is similar to the hand feel provided by trilobal and round shaped filaments, but the melt-spun filaments are less prone to breaking (higher tenacity) than trilobal and round shaped filaments, which also reduces waste.

In some implementations, a bundle of filaments that includes a plurality of the melt-spun filaments is provided. In some implementations, a filament yarn that includes a plurality of the melt-spun filaments is provided. And, in some implementations, a bulked continuous filament yarn that includes a plurality of melt-spun filaments is provided.

According to some implementations, the melt-spun filament is made by (1) providing a spinneret plate comprising one or more capillaries, each capillary having a rectangular shaped outlet opening; and (2) feeding at least one melted thermoplastic polymer through the capillary.

For example, FIGS. 1 and 2 illustrate an example melt-spun filament according to one implementation. FIG. 1 shows a radial cross section of the melt-spun filament 10. The radial cross section of the melt-spun filament 10 has a first linear perimetrical section 12, a second linear perimetrical section 14, a first curved perimetrical section 16, and a second curved perimetrical section 18. The term “section” as used herein refers to portions of an external surface of the filament. The first curved perimetrical section 16 extends between first ends 12 a, 14 a of the first and second linear perimetrical sections 12, 14, respectively, and the second curved perimetrical section 18 extends between second ends 12 b, 14 b of the linear perimetrical sections 12, 14, respectively. The curved perimetrical sections 16, 18 are convex as viewed from a point external to the filament 10 in a direction toward the filament 10. In other words, these sections 16, 18 appear concave as viewed in a direction toward the sections 16, 18 from an axis A-A of the melt-spun filament 10. As shown, the curved perimetrical sections 16, 18, are curved, or arcuate shaped, along the entire length of the sections 16, 18 extending between ends 12 a, 14 a and 12 b, 14 b of the linear perimetrical sections 12, 14, respectively. Accordingly, the radial cross section of the melt-spun filament 10 appears capsule shaped. The filament 10 is solid. Accordingly, the filament 10 does not define a void or hollow portion that extends axially through the filament 10.

The curved perimetrical sections have a radius of curvature that is less than any radius of curvature of the linear perimetrical sections. In particular, to the extent that the linear perimetrical sections are curved, the curvature of each linear perimetral section has a radius that is significantly greater than the radius of the curvature of each of the curved perimetral section. For example, a tangent line to the ends of the linear perimetrical sections is between 0° to 10° relative to a plane that extends axially through the melt-spun filament and intersects (e.g., bisects) the curved perimetral sections and includes the central axis of the filament. Due to the expansion of material as it exits the spinneret and the pulling of the filament after it exits the spinneret, the linear perimetrical sections are not perfectly linear. In other words, some curvature with a large radius is expected for these linear perimetral sections.

According to some embodiments, the filament 10 comprises a thermoplastic material. For example, according to one embodiment, the thermoplastic material is selected from the group consisting of: polytrimethylene terephthalate (PTT), polyethylene terephthalate (PET), polyamides (PA), Polybutylene terephthalate (PBT), and other polyesters and polyolefins. Example polyamides include nylon 6 and nylon 6,6. Example polyolefins include polypropylene (PP) and polyethylene (PE). And, in some embodiments, the first or second material may include a polyolefin and a carbon filler to produce an antistatic yarn. The thermoplastic material resin may be virgin or reclaim grade, according to some embodiments.

According to some embodiments, a width W_(F) to height H_(F) ratio of the radial cross section of the filament 10 is between 3.5:1 and 1.5:1. The width W_(F) is measured in a direction of the linear perimetrical sections 12, 14 at the widest points of the radial cross section, and the height H_(F) is measured in a direction perpendicular to the length direction. For example, according to some embodiments, the width W_(F) to height H_(F) ratio of the radial cross section is between 3:1 and 2.2:1. In certain embodiments in which the filament 10 is spun through capillaries having a 4:1 width to height ratio (such as shown in FIGS. 5A-5C), the width W_(F) to height H_(F) ratio is between 2.5:1 and 2.2:1. In certain embodiments in which the filament 10 is spun through capillaries having a 6:1 width to height ratio (such as shown in FIGS. 6A-6C), the width W_(F) to height H_(F) ratio is between 3:1 to 2.8:1. The titer per fiber or filament (also referred to as “denier per filament”, “denier per fiber” or “dpf”) range is between 2 and 5 dpf.

FIGS. 5A-5B illustrate views of a capillary 50 in a spinneret plate used for spinning melted thermoplastic material into the filament 10, and FIG. 5C illustrates a portion of a spinneret plate 100 defining a plurality of capillaries 50. The capillary 50 has a width W_(C) to height H_(C) ratio of 4:1. The ratio may also be referred to a spin slot aspect ratio. Photographs of sample filaments spun from a spinneret, such as spinneret 100, having multiple capillaries 50 are shown in FIGS. 4A and 4B. The filaments 10 shown in FIG. 4A are spun from a spinneret having 87 capillaries 50, and the filaments have a denier per filament of 3.8 denier. The filaments 10 shown in FIG. 4B are spun from a spinneret having 120 capillaries 50, and the filaments have a denier per filament of 2.8 denier. In addition, each capillary 50 has a first end portion 51 and a second end portion 52 and an intermediate portion 53 therebetween. The intermediate portion 53 has a constant radial cross-sectional area along the length of the capillary 50. Each end portion is tapered. The surface of each tapered end portion 51, 52 slants at an angle α. The angle α may be between 45° and 80°. For example, in FIGS. 5A-5B, the angle α is 45°. The first end portion 51 has a radial cross-sectional area that decreases axially from a first end 51 a of the first end portion 51 to a second end 51 b of the first end portion 51, wherein the first end 51 a is defined by a first surface 100 a of the spinneret plate 100. The second end portion 52 has a radial cross-sectional area that decreases axially from a first end 52 a of the second end portion 52 to a second end 52 b of the second end portion 52, wherein the second end 52 b is defined by a second surface 100 b of the spinneret plate 100.

The ratio of the number of filaments per yarn spun into the shape shown in FIGS. 1 and 2 compared to the number of trilobal or round filaments spun into a yarn having a similar hand feel is about 1:2. For example, there may be 160 filaments per bundle or yarn for filaments having the shape shown in FIGS. 1 and 2 , compared to 320 trilobal or round filaments in a yarn having similar hand feel.

In other implementations, the melt-spun filament 10 is converted into a plurality of staple fibers. Staple fibers have shorter lengths, such as 2 to 3 inches long, compared to filaments, which have long continuous lengths. For example, the melt-spun filament may be converted to a plurality of staple fibers by stretch breaking or chopping one or more of such melt-spun filaments. And, in some implementations, a plurality of the staple fibers may be bundled.

According to some implementations, the filament 10 is made by (1) providing a spinneret plate comprising one or more capillaries, each capillary having a rectangular shaped outlet opening; and (2) feeding at least one melted thermoplastic polymer through the capillary. For example, the spinneret plate may be the spinneret plate 100 shown in FIG. 5C having capillaries 50. Various factors contribute to the shape and denier per filament of the filaments, including the melt temperature, the speed of the pump in communication with the extruder, the draw ratio, and the rate at which the filaments are cooled. Altering one or more of these factors can provide the desired shape. For example, if the pump speed is increased but all other factors remain the same, the denier per filament is increased. If the draw ratio is increased and all other factors remain the same, the denier per filament is decreased and the aspect ratio decreases (e.g., from 4:1 to 4:1.5). As another example, if the cooling rate is increased and all other factors remain the same, the cross-sectional shape of the filament is more defined.

In other implementations, the spinneret plate may be spinneret plate 200 shown in FIG. 6C having capillaries 60. A radial cross section of one of capillaries 60 is shown in FIG. 6A, and an axial cross section of the capillary in FIG. 6A is shown in FIG. 6B. Capillary 60 is similar to capillary 50 except that the width to height ratio of the capillary is 6:1. Photographs of sample filaments spun from a spinneret, such as spinneret 200, having multiple capillaries 60 are shown in FIGS. 3A and 3B. The filaments 10 shown in FIG. 3A are spun from a spinneret having 87 capillaries 60, and the filaments have a denier per filament of 3.8. The filaments 10 shown in FIG. 4B are spun from a spinneret having 120 capillaries 60, and the filaments have a denier per filament of 2.8. In addition, each capillary 60 has a first end portion 61 and a second end portion 62 and an intermediate portion 63 therebetween. The intermediate portion 63 has a constant radial cross-sectional area along the length of the capillary 60. Each end portion is tapered. The surface of each tapered end portion 61, 62 slants at an angle α. The angle α may be between 45° and 80°. For example, in FIGS. 6A-6B, the angle α is 45°. The first end portion 61 has a radial cross-sectional area that decreases axially from a first end 61 a of the first end portion 61 to a second end 61 b of the first end portion 61, wherein the first end 61 a is defined by a first surface 200 a of the spinneret plate 200. The second end portion 62 has a radial cross-sectional area that decreases axially from a first end 62 a of the second end portion 62 to a second end 62 b of the second end portion 62, wherein the second end 62 b is defined by a second surface 200 b of the spinneret plate 200.

FIG. 7 illustrates a melt-spun filament 20 according to another implementation. The substantially linear perimetrical sections are slightly arcuate shaped compared to the linear perimetrical sections in FIGS. 1 and 2 , but the linear perimetrical sections are significantly less curved compared to the curved perimetrical sections. For example, the radial cross section of the melt-spun filament 20 shown in FIG. 7 is rice shaped. The angle of a tangent line T to the ends 22 a, 22 b, 24 a, 24 b of the linear perimetrical sections 22, 24, respectively, that intersects the curved perimetrical section 26, 28 may be between 0° and 10° relative to a plane P that extends axially through the melt-spun filament 20 and includes central axis A-A and intersects the curved perimetrical sections 26, 28.

According to some embodiments, the melt-spun filament further comprises a core and a sheath disposed around the core. For example, FIG. 8 illustrates a melt-spun filament 30 having a core 31 and sheath 33. The core 31 is formed from a first material, and the sheath 33 is formed from a second material. In some implementations, the first material and the second material are different. For example, according to some embodiments, the first material and the second material are selected from the group consisting of polytrimethylene terephthalate (PTT), polyethylene terephthalate (PET), polyamide (PA), Polybutylene terephthalate (PBT), and other polyesters and polyolefins. The core 31 and the sheath 33 each have two linear perimetrical sections and two curved perimetrical sections, such as are described in relation to FIGS. 1, 2, and 7 above.

According to some embodiments, the melt-spun filament comprises a first material and a second material that are coupled along a plane that includes the axis of the fiber, and the first material and second material have different coefficients of thermal expansion. For example, FIG. 9 shows a melt-spun filament 40 according to one implementation that includes a first material 41 on one side of the plane P′ that includes the axis of the filament 40 and intersects the curved perimetrical sections 46, 48 of the filament 40 and a second material 43 on the other side of the plane P′. In some implementations, the first material and the second material are selected from the group consisting of polytrimethylene terephthalate (PTT), polyethylene terephthalate (PET), polyamide (PA), Polybutylene terephthalate (PBT), and other polyesters and polyolefins. The linear perimetrical section and the portions of the curved perimetrical sections for each material together come together after spinning to form one filament having two linear perimetrical sections and two curved perimetrical sections, such as are described in relation to FIGS. 1, 2, and 7 above. The bi-component melt-spun filament 40 is self-bulking, according to some implementations, due to the different coefficients of thermal expansion for each material.

Like the first filament 10, the other filaments 20, 30, 40 are solid. Accordingly, the other filaments 20, 30, 40 do not define void or hollow portions that extend axially through the other filaments 20, 30, 40.

In another embodiment of the inventions disclosed and taught herein, the capillaries may be configured with a counterbore section below the second angled portion.

FIGS. 10A-10B illustrate views of a capillary 1050 in a spinneret plate used for spinning melted thermoplastic material into the filament 10, and FIG. 10C illustrates a portion of a spinneret plate 1010 defining a plurality of capillaries 1050. Each capillary 1050 has a width W_(C) to height H_(C) ratio of 4:1. The ratio may also be referred to a spin slot aspect ratio. In addition, each capillary 1050 has a first tapered portion 1051, an intermediate portion 1053 adjacent, a lower tapered portion 1052, and a counterbore 1055. The intermediate portion 1053 has a constant radial cross-sectional area along the length of the capillary 1050. This radial cross-sectional area is illustrated in FIG. 10A. The angled end portion 1051 is tapered as is the intermediate tapered portion 1052. The surface of each tapered portion 1051, 1052 slants at an angle α. The angle α may be between 45° and 80°. For example, in FIG. 10A, the angle α is 60°. The top end portion 1051 has a radial cross-sectional area that decreases axially from a first end 1051 a of the top end portion 1051 to a second end 1051 b of the top tapered portion 1051, wherein the first end 1051 a is defined by a first surface 1010 a of the spinneret plate 1010. The intermediate angled portion 1052 has a radial cross-sectional area that decreases axially from a first end 1052 a of the intermediate tapered portion 1052 to a second end 1052 b of the intermediate tapered portion 1052, wherein the second end 1052 b is defined by a transition to the adjacent counterbore 1055.

FIG. 10C illustrates a section of spinneret plate 1010 as seen from the extrusion side 1010 b with three exemplary capillaries 1050.

The counterbore 1055 has sides that are perpendicular to the surface 1010 b of the spinneret plate 1010 with a length L_(CB). Optimal filaments have been produced using a counterbore 1055 with a length of between about 0.010 inches and about 0.025 inches. Filaments exhibiting the properties disclosed herein may be made with counterbores having longer or shorter lengths as well.

Various factors contribute to the shape and denier per filament of the filaments, including the melt temperature, the speed of the pump in communication with the extruder, the draw ratio, and the rate at which the filaments are cooled. Altering one or more of these factors can provide the desired shape. For example, if the pump speed is increased but all other factors remain the same, the denier per filament is increased. If the draw ratio is increased and all other factors remain the same, the denier per filament is decreased and the aspect ratio decreases (e.g., from 4:1 to 4:1.5). As another example, if the cooling rate is increased and all other factors remain the same, the cross-sectional shape of the filament is more defined.

In other implementations, the spinneret plate may be spinneret plate 1110 shown in FIG. 11C having capillaries 1150. A radial cross section of one of capillaries 1150 is shown in FIG. 11A, and an axial cross section of the capillary in FIG. 11B is shown in FIG. 12A. Capillary 1150 is similar to capillary 1050 except that the width to height ratio of the capillary 1150 is 6:1. In addition, each capillary 1150 has a first tapered portion 1151 and a counterbore 1155 and an intermediate portion 1153 with a second tapered portion 1152 therebetween. The intermediate portion 1153 has a constant radial cross-sectional area along the length of the capillary 1150. The top tapered portion 1151 is angled as is the intermediate tapered portion 1152. The surface of each tapered end portion 1151, 1152 may slant at an angle α. The angle α may be between 45° and 80°. For example, in FIG. 11B, the angle α is 60°. The top tapered portion 1151 has a radial cross-sectional area that decreases axially from a first tapered end 1151 a of the top end portion 1151 to a second end 1151 b of the top tapered portion 1151, wherein the first tapered end 1151 a is defined by a first surface 1110 a of the spinneret plate 1110. The intermediate angled portion 1152 has a radial cross-sectional area that decreases axially from a first end 1152 a of the intermediate angled portion 1152 to a second end 1152 b of the intermediate angled portion 1152, wherein the second end 1152 b is defined by a transition to the counterbore 1155.

FIG. 11C illustrates a section of spinneret plate 1110 as seen from the extrusion side 1110 b with three exemplary capillaries 1150.

The counterbore 1155 has sides that are perpendicular to the surface 1110 b of the spinneret plate 1110 with a length L_(CB). Optimal filaments have been produced using a counterbore 1155 with a length of between about 0.010 inches and about 0.025 inches. Filaments exhibiting the properties disclosed herein may be made with counterbores having longer or shorter lengths as well.

Various factors contribute to the shape and denier per filament of the filaments, including the melt temperature, the speed of the pump in communication with the extruder, the draw ratio, and the rate at which the filaments are cooled. Altering one or more of these factors can provide the desired shape. For example, if the pump speed is increased but all other factors remain the same, the denier per filament is increased. If the draw ratio is increased and all other factors remain the same, the denier per filament is decreased and the aspect ratio decreases (e.g., from 6:1 to 6:1.5). As another example, if the cooling rate is increased and all other factors remain the same, the cross-sectional shape of the filament is more defined.

FIG. 12A illustrates a cross section of an exemplary capillary with a polymer flowing through it. Similarly, FIG. 12B illustrates the cross section of the exemplary capillary from a right-angle view from FIG. 12A. In the process of producing a filament 10, any of the polymers disclosed herein, or combinations of them, may be pumped through the capillary 1250. The polymer will enter the first tapered portion 1251 and be compressed from the inward taper of the sides. The molten polymer will again be compressed at the intermediate tapered portion 1252 and will be extruded through the counterbore 1255.

Immediately upon exiting the counterbore 1255, the molten polymer has been observed to swell and bulge outwardly from the centerline of the capillary 1250. The draw down force, represented as F_(d) in FIGS. 12A and 12B, extends the polymer into a filament 10 with a resulting cross section as has been described. That is to say that in certain embodiments in which the filament 10 is spun through capillaries having a 4:1 width to height ratio (such as shown in FIGS. 10A-10C), the width W_(F) to height H_(F) ratio of the filaments 10 may be between 2.5:1 and 2.2:1. In certain embodiments in which the filament 10 is spun through capillaries having a 6:1 width to height ratio (such as shown in FIGS. 11A-11C), the width W_(F) to height H_(F) ratio may be between 3:1 to 2.8:1. Those of ordinary skill and in possession of the inventions disclosed and taught herein will understand that other width to height ratios may be obtained that will yield filaments with the properties and characteristics as described herein.

Since the pump is responsible for the throughput or velocity of the polymer melt through the capillaries, increasing the depth of the counterbore may be used to cause a greater pressure drop through that capillary and then cause more shear differential across the filament. That is to say that the middle of the polymer melt will travel faster than the edges as it is extruded from the capillary.

This pressure drop, in turn, will cause different stresses and alignments to form in the polymer melt that may be exploited to cause changes in the resulting bulk of the yarn.

As the filament 10 is being drawn down, it will have a first filament aspect ratio at a point near the spinneret plate, and a second filament aspect ratio at a point further away from the spinneret plate. That is to say that as the filament will no longer retain an aspect ratio similar to that of the counterbore as it is drawn, but will change to have a different aspect ratio at a point further away from the counterbore of the spinneret plate.

The titer per fiber or filament (also referred to as “denier per filament”, “denier per fiber” or “dpf”) range using the processes disclosed and taught herein may be between 2 and 5 dpf. Those of ordinary skill in the art and in possession of the teachings and disclosures herein will be able to envision and produce other dpf ranges without departing from the spirit of the inventions disclosed and taught herein.

The following two tables represent without limitation the characteristics of filaments that may be spun from different capillaries under different influences. Table 1 represents the characteristics of filaments spun from capillaries having a spin slot aspect ratio of 4:1, and Table 2 represents the characteristics of filaments spun from capillaries having a spin slot aspect ratio of 6:1.

TABLE 1 L_(CB) F_(d) Bulk Feel Short Low Low Slick Short Hi Low Slick Long Low Medium Slick Long Hi Medium Slick

TABLE 2 L_(CB) F_(d) Bulk Feel Short Low Medium Soft Short Hi Medium Soft Long Low High Soft Long Hi High Soft

As may be seen from tables 1 and 2, filaments produced with longer counterbore depths—those near or around 0.025 inches—produce filaments with higher bulk and softer feel than those produced with shorter counterbore depths—those near or around 0.010 inches. Since the pressure may be considered to be a by-product of the throughput, temperature of the polymer, and the capillary design, controlling the pressure may also affect the stress placed upon the polymer to allow for the configuration of the resulting bulk.

Table 3 represents without limitations a set of exemplary properties of yarns produced using the inventions disclosed and taught herein. Two spinneret plates were connected to a single hanger from an extruder and filaments were produced from a polymer melt extruded through the capillaries. The left spinneret plate was configured with capillaries configured in a 6:1 spin slot aspect ratio, while the right spinneret plate was configured with capillaries configured in a 4:1 spin slot aspect ratio. All other parameters of the pump rate, quench, and draw were the same. Both sets of capillaries had a short length of near 0.010 inches. That is to say that the F_(d) was “Low”.

Spinneret Plate Denier FOY Tenacity Elongation % TR Crimp Shrink Left 6:1 1204 0.800 2.900 51.20 8.49-9.40 4.15-4.37 4.53-5.26 Right 4:1 1223 0.725 2.885 48.65 9.38-9.61 5.14-5.15 5.56-5.70

In general, then, using the inventions disclosed and taught herein, the production of self-bulking yarn may be achieved by extruding polymer melt through a capillary with a high depth of the counterbore, having a 6:1 spin slot aspect ratio with a high melt temperature. The extruded polymer melt may then be processed with a low quench temperature with high quench flow and humidity, along with a minimum required draw ratio with high temperatures on the godets. A low dpf/filament count spinneret may be used to obtain a bulkier fiber that will have greater coverage. Similarly, for a softer feel, a higher filament count spinneret may be used.

Similarly, using the inventions disclosed and taught herein, the production of a soft yarn may be achieved by extruding polymer melt through a capillary with a 4:1 spin slot aspect ratio with a low depth of the counterbore in a high filament count spinneret. The extruded polymer melt may then be processed with a low quench temperature and with the draw ratios maximized with minimal temperatures on the godets. The resulting yarn will feel slick and soft. To obtain improved coverage by the yarn in the carpet, a deeper counterbore (a “Hi” counterbore such as near or about 0.025 inches) in the spinneret may be configured with all other parameters kept the same. This configuration and processing may cause more twisting on a macro scale and leave the yarn soft with more bulk.

Various implementations have been described. Nevertheless, it will be understood that various modifications may be made without departing from the spirit and scope of the description. Accordingly, other implementations are within the scope of the following claims.

Disclosed are materials, systems, devices, methods, compositions, and components that can be used for, can be used in conjunction with, can be used in preparation for, or are products of the disclosed methods, systems, and devices. These and other components are disclosed herein, and it is understood that when combinations, subsets, interactions, groups, etc. of these components are disclosed that while specific reference of each various individual and collective combinations and permutations of these components may not be explicitly disclosed, each is specifically contemplated and described herein. For example, if a device is disclosed and discussed every combination and permutation of the device, and the modifications that are possible are specifically contemplated unless specifically indicated to the contrary. Likewise, any subset or combination of these is also specifically contemplated and disclosed. This concept applies to all aspects of this disclosure including, but not limited to, steps in methods using the disclosed systems or devices. Thus, if there are a variety of additional steps that can be performed, it is understood that each of these additional steps can be performed with any specific method steps or combination of method steps of the disclosed methods, and that each such combination or subset of combinations is specifically contemplated and should be considered disclosed. 

1.-72. (canceled)
 73. A spinneret plate for producing a self-bulking melt-spun filament comprising: at least one capillary comprising: a first section comprising a counterbore with vertical sides; wherein the counterbore comprises a depth of between about 0.010 inches and about 0.025 inches; a second section comprising angled sides of a first angle; a third section comprising vertical sides; a fourth section comprising angled sides of a second angle; wherein a cross-section of the at least one capillary comprises a rectangle; and wherein a rectangular cross-section comprises a width and a height, and wherein a spin slot aspect ratio is the ratio of the width to the height in the counterbore of the capillary.
 74. The spinneret plate according to claim 73, wherein the spin slot aspect ratio is selected from the group consisting of about 4:1 or about 6:1.
 75. The spinneret plate according to claim 73, wherein the first angle is between 45° and 80°.
 76. The spinneret plate according to claim 73, wherein the second angle is between 45° and 80°.
 77. The spinneret plate according to claim 73, wherein the first angle is equal to the second angle.
 78. A method for producing a melt-spun filament from the capillary according to claim 73 comprising: pumping a polymer melt into the capillary at a first speed to produce a filament having a first filament aspect ratio at the spinneret plate; drawing the filament at a first draw rate from the spinneret plate such that the filament has a second filament aspect ratio at a point further away from the spinneret plate.
 79. The melt-spun filament produced from the capillary according to claim 78, wherein the radial cross section is capsule shaped.
 80. The melt-spun filament produced from the capillary according to claim 78, wherein the radial cross section is rice shaped.
 81. The melt-spun filament produced from the capillary according to claim 78, wherein a plane extending axially through the melt-spun filament intersects the curved perimetrical ends and includes a central axis of the filament, and a line that is tangential to one of the ends of the linear perimetrical sections intersects the plane at an angle of between 0° and 10°.
 82. The melt-spun filament produced from the capillary according claim 78, further comprising a core and a sheath disposed around the core, the core being formed from a first material, and the sheath being formed from a second material.
 83. The melt-spun filament produced from the capillary according to claim 82, wherein the first material and the second material are selected from the group consisting of polytrimethylene terephthalate (PTT), polyethylene terephthalate (PET), polyamides (PA), Polybutylene terephthalate (PBT), other polyesters and polyolefins, or combinations thereof.
 84. A method for producing a self-bulking melt-spun filament comprising: providing a spinneret plate comprising at least one capillary, wherein the capillary comprises: a rectangular opening with a first section comprising a counterbore having substantially vertical sides that are perpendicular to a face of the spinneret plate; a second section adjoining the first section, wherein the second section comprises sides that are angled away from the vertical sides of the first section at a first angle; a third section adjoining the second section, wherein the third section comprises sides that are substantially vertical; a fourth section adjoining the third section, wherein the fourth section comprises sides that are angled away from the vertical sides of the third section at a second angle; pumping a polymer melt into the fourth section of the capillary at a first speed to extrude a filament from the counterbore, wherein the filament has a first filament aspect ratio at the spinneret plate; drawing the filament at a first draw rate from the spinneret plate such that the filament has a second filament aspect ratio at a point further away from the spinneret plate.
 85. The melt-spun filament according to claim 84, wherein the radial cross section is capsule shaped.
 86. The melt-spun filament according to claim 84, wherein the radial cross section is rice shaped.
 87. The melt-spun filament according to claim 84, wherein a plane extending axially through the melt-spun filament intersects the curved perimetrical ends and includes a central axis of the filament; and wherein a line that is tangential to one of the ends of the linear perimetrical sections intersects the plane at an angle of between 0° and 10°.
 88. The capillary according to claim 84, wherein the counterbore comprises a depth of between about 0.010 inches and about 0.025 inches.
 89. The capillary according to claim 84, wherein the first angle is between 45° and 80°.
 90. The capillary according to claim 84, wherein the second angle is between 45° and 80°.
 91. The capillary according to claim 84, wherein the first angle is equal to the second angle.
 92. The melt-spun filament produced from the capillary according to claim 82, wherein the first material and the second material are selected from the group consisting of polytrimethylene terephthalate (PTT), polyethylene terephthalate (PET), polyamides (PA), Polybutylene terephthalate (PBT), other polyesters and polyolefins, or combinations thereof. 